"I'm writing to urge the panel to uphold this ban, which is in line with the wishes of compassionate people all around the world, including the majority of European citizens," wrote Law in his letter to the WTO.
"Even local sentiment is turning, and a lack of markets has led Canadian officials to seriously examine whether the slaughter should end."
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Law also said that it was time for Canada to abandon the seal hunt altogether and for the government to buy out the industry.
"The purpose of the WTO is to support efficient markets, not government decisions to prop up dying industries like the seal slaughter," Law pointed out.
"Rather than using the WTO to prop up a dying industry, Canada should pursue a buyout of the commercial sealing industry – a move that would help both seals and sealers. The world is watching and waiting – please uphold the EU ban."